Refrigeration cycle device

ABSTRACT

A refrigeration cycle device includes an outside evaporator, an inside evaporator, an evaporating pressure adjusting valve, a charging port, a pressure change buffer. The outside evaporator exchanges heat between a refrigerant flowing out of a heater and an outside air. The inside evaporator exchanges heat between the refrigerant flowing out of the outside evaporator and a heat-exchange target medium. The evaporating pressure adjusting valve is disposed at a position downstream of the inside evaporator and adjusts an evaporating pressure of the refrigerant in the inside evaporator. The charging port is disposed at a position downstream of the evaporating pressure adjusting valve. The pressure change buffer is disposed between the evaporating pressure adjusting valve and the charging port and defines a buffer space.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation application of InternationalPatent Application No. PCT/JP2018/041810 filed on Nov. 12, 2018, whichdesignated the U.S. and claims the benefit of priority from JapanesePatent Application No. 2017-233196 filed on Dec. 5, 2017. The entiredisclosures of all of the above applications are incorporated herein byreference.

TECHNICAL FIELD

The present disclosure relates to a refrigeration cycle device.

BACKGROUND ART

A refrigeration cycle device includes a compressor, an outsideevaporator, an inside evaporator, and an evaporating pressure adjustingvalve. The evaporating pressure adjusting valve is configured to adjustan evaporating pressure of a refrigerant in the inside evaporator as avalue equal to or higher than a frost restriction pressure to restrict afrost from generating on the inside evaporator. The evaporating pressureadjusting valve is configured to adjust an opening degree of the valvewith a mechanical means.

SUMMARY

A refrigeration cycle device includes a compressor, a heater, an insideevaporator, an outside evaporator, a first refrigerant passage, a firstdecompressor, a second refrigerant passage, a second decompressor, anevaporating pressure adjusting valve, a third refrigerant passage, anopening-closing member, a charging port, and a pressure change buffer.The compressor compresses and discharges a refrigerant. The heater heatsa heat-exchange target fluid using the refrigerant, as a heat source,discharged from the compressor. The outside evaporator exchanges heatbetween an outside air and the refrigerant flowing out of the heater.The inside evaporator exchanges heat between the refrigerant flowing outof the outside evaporator and the heat-exchange target fluid. Therefrigerant flowing out of the heater is guided toward an inlet of theoutside evaporator through the first refrigerant passage. The firstdecompressor is disposed in the first refrigerant passage and configuredto vary an opening area of the first refrigerant passage. Therefrigerant flowing out of the outside evaporator flows through theinside evaporator toward a suction inlet of the compressor through thesecond refrigerant passage. The second decompressor is disposed in thesecond refrigerant passage between the outside evaporator and the insideevaporator and configured to vary an opening area of the secondrefrigerant passage. The evaporating pressure adjusting valve isdisposed in the second refrigerant passage at a position downstream ofthe inside evaporator and configured to adjust an evaporating pressureof the refrigerant in the inside evaporator. The third refrigerantpassage has an end fluidly connected to a portion of the secondrefrigerant passage between the evaporating pressure adjusting valve andthe compressor. The refrigerant flowing out of the outside evaporator isguided toward the suction inlet of the compressor through the thirdrefrigerant passage. The charging port through which the refrigerant issupplied is disposed in the second refrigerant passage at a positiondownstream of the evaporating pressure adjusting valve. The pressurechange buffer is disposed in the second refrigerant passage between theevaporating pressure adjusting valve and the charging port and defines abuffer space to restrict an inner pressure in the second refrigerantpassage from rapidly changing when the refrigerant is supplied throughthe charging port

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram of an air conditioner including a refrigerationcycle device according to a first embodiment.

FIG. 2 is a diagram of an air conditioner including a refrigerationcycle device according to a second embodiment.

FIG. 3 is a diagram of an air conditioner including a refrigerationcycle device according to a third embodiment.

DESCRIPTION OF EMBODIMENTS

To begin with, examples of relevant techniques will be described.

A refrigeration cycle device includes a compressor, an outsideevaporator, an inside evaporator, and an evaporating pressure adjustingvalve. The evaporating pressure adjusting valve is configured to adjustan evaporating pressure of a refrigerant in the inside evaporator as avalue equal to or higher than a frost restriction pressure to restrict afrost from generating on the inside evaporator. The evaporating pressureadjusting valve is configured to adjust an opening degree of the valvewith a mechanical means.

The refrigeration cycle device includes a high-pressure charging port ata position downstream of the compressor to supply the refrigerant beforeshipping the cycle device. The refrigeration cycle device includes alow-pressure charging port at a downstream of a low-pressure evaporatorto supply the refrigerant after shipping the cycle device.

The evaporating pressure adjusting valve of the refrigeration cycledevice varies the opening degree of the valve according to a pressuredifference between the refrigerant upstream of the valve and therefrigerant downstream of the valve. When the pressure of therefrigerant downstream of the valve exceeds the pressure of therefrigerant upstream of the valve and thus a counter pressure is appliedto the evaporating pressure adjusting valve, a durability of theevaporating pressure adjusting valve may be impaired. Thus, thelow-pressure charging port is typically disposed at a position upstreamof the evaporating pressure adjusting valve.

As described above, it is difficult to arrange the low-pressure chargingport at a position downstream of the evaporating pressure adjustingvalve, and therefore a flexibility of positions at which thelow-pressure charging port is disposed is limited. Thus, there has beendemand for a refrigeration cycle device that can keep a durability ofthe evaporating pressure adjusting valve even though the low-pressurecharging port is positioned downstream of the evaporating pressureadjusting valve.

It is objective of the present disclosure to provide a refrigerationcycle device that has a high flexibility in positioning of a chargingport without impairing a durability of an evaporating pressure adjustingvalve.

According to one aspect of the present disclosure, a refrigeration cycledevice includes a compressor, a heater, an inside evaporator, an outsideevaporator, a first refrigerant passage, a first decompressor, a secondrefrigerant passage, a second decompressor, an evaporating pressureadjusting valve, a third refrigerant passage, an opening-closing member,a charging port, and a pressure change buffer. The compressor compressesand discharges a refrigerant. The heater heats a heat-exchange targetfluid using the refrigerant, as a heat source, discharged from thecompressor. The outside evaporator exchanges heat between an outside airand the refrigerant flowing out of the heater. The inside evaporatorexchanges heat between the refrigerant flowing out of the outsideevaporator and the heat-exchange target fluid. The refrigerant flowingout of the heater is guided toward an inlet of the outside evaporatorthrough the first refrigerant passage. The first decompressor isdisposed in the first refrigerant passage and configured to vary anopening area of the first refrigerant passage. The refrigerant flowingout of the outside evaporator flows through the inside evaporator towarda suction inlet of the compressor through the second refrigerantpassage. The second decompressor is disposed in the second refrigerantpassage between the outside evaporator and the inside evaporator andconfigured to vary an opening area of the second refrigerant passage.The evaporating pressure adjusting valve is disposed in the secondrefrigerant passage at a position downstream of the inside evaporatorand configured to adjust an evaporating pressure of the refrigerant inthe inside evaporator. The third refrigerant passage has an end fluidlyconnected to a portion of the second refrigerant passage between theevaporating pressure adjusting valve and the compressor. The refrigerantflowing out of the outside evaporator is guided toward the suction inletof the compressor through the third refrigerant passage. The chargingport through which the refrigerant is supplied is disposed in the secondrefrigerant passage at a position downstream of the evaporating pressureadjusting valve. The pressure change buffer is disposed in the secondrefrigerant passage between the evaporating pressure adjusting valve andthe charging port and defines a buffer space to restrict an innerpressure in the second refrigerant passage from rapidly changing whenthe refrigerant is supplied through the charging port

The pressure change buffer can restrict the inner pressure in the secondrefrigerant passage, in which the evaporating pressure adjusting valveis disposed, from rapidly changing when the refrigerant is supplied tothe refrigeration cycle device through the charging port. Thus, apressure change at an outlet side of the evaporating pressure adjustingvalve can be suppressed. As a result, a durability of the evaporatingpressure adjusting valve can be restricted from deteriorating eventhough the charging port is disposed at a position downstream of theevaporating pressure adjusting valve.

According to the present disclosure, it is possible to flexibly select aposition for the charging port without impairing a durability of theevaporating pressure adjusting valve.

Hereinafter, embodiments for implementing the present disclosure will bedescribed with reference to drawings. In the respective embodiments,parts corresponding to matters already described in the precedingembodiments are given reference numerals identical to reference numeralsof the matters already described. The same description is thereforeomitted depending on circumstances. When only a part of a configurationis described in an embodiment, another preceding embodiment may beapplied to the other parts of the configuration. The present disclosureis not limited to combinations of embodiments which combine parts thatare explicitly described as being combinable. As long as no problem ispresent, the various embodiments may be partially combined with eachother even if not explicitly described.

First Embodiment

An air conditioner 1 including a refrigeration cycle device 10 in afirst embodiment will be described with reference to FIG. 1. The airconditioner 1 includes the refrigeration cycle device 10, a heater 25,and an inside air-conditioning unit 30. In this embodiment, therefrigeration cycle device 10 is applied to the air conditioner 1mounted in an electric vehicle that obtains a driving force from anelectric motor for driving. The refrigeration cycle device 10 of the airconditioner 1 cools and heats a ventilation air conveyed to a vehiclecabin that is an air-conditioning target space. A heat-exchange targetfluid in this embodiment is the ventilation air.

The refrigeration cycle device 10 is configured to switch therefrigerant circuit between a heating mode, a cooling mode, a serialdehumidification heating mode, and a parallel dehumidification heatingmode.

The heating mode of the air conditioner 1 is an operating mode in whicha ventilation air is heated and conveyed to the vehicle cabin that isthe air-conditioning target space. The serial dehumidification heatingmode and the parallel dehumidification heating mode are operating modesin which the ventilation air having been cooled and dehumidified isheated and conveyed into the vehicle cabin that is the air-conditioningtarget space. The cooling mode is an operating mode in which theventilation air is cooled and conveyed to the vehicle cabin that is theair-conditioning target space.

In FIG. 1, a flow of a refrigerant in the refrigerant circuit of theheating mode is indicated by black arrows and a flow of the refrigerantin the refrigerant circuit of the parallel dehumidification heating modeis indicated by arrows with diagonal hatching. A flow of the refrigerantin the refrigerant circuit of the serial dehumidification heating modeand the cooling mode are indicated by white arrows.

The refrigeration cycle device 10 uses a hydrofluorocarbon typerefrigerant (i.e., HFC type refrigerant and specifically, R134a) as arefrigerant and constitutes a vapor compression type subcriticalrefrigerant cycle in which a pressure of a high pressure siderefrigerant Pd does not exceed a critical pressure of the refrigerant.However, a hydrofluoroolefin type refrigerant (i.e., HFO typerefrigerant) such as R1234yf may be used as the refrigerant. Inaddition, the refrigerant contains a refrigerant oil to lubricate acompressor 11 and a part of the refrigerant oil circulates through thecycle together with the refrigerant.

The refrigeration cycle device 10 includes the compressor 11, acondenser 12, a first decompression valve 15 a (a first decompressor), asecond decompression valve 15 b (a second decompressor), an outsideevaporator 16, a non-return valve 17, an inside evaporator 18, anevaporating pressure adjusting valve 19, an accumulator 20 (a pressurechange buffer), a first opening-closing valve 21 (an opening-closingmember), a second opening-closing valve 22, a low-pressure charging port23, and a high-pressure charging port 24.

The compressor 11 sucks, compresses, and discharges the refrigerant inthe refrigeration cycle device 10. The compressor 11 is disposed in anengine compartment of the vehicle. The compressor 11 is configured as anelectric compressor in which a fixed-displacement type compressionmechanism is driven by an electric motor. The fixed-displacement typecompression mechanism has a fixed discharging capacity and may applyvarious types of compression mechanisms such as a scroll typecompression mechanism and a vane type compression mechanism.

The operation of the electric motor such as a rotational speed iscontrolled by control signals outputted from an air conditioningcontroller. The electric motor may be an alternate current motor ordirect current motor. The air conditioning controller controls therotational speed of the electric motor to alter a refrigerantdischarging capacity of the compression mechanism.

A discharge outlet of the compressor 11 is fluidly connected to arefrigerant inlet of the condenser 12. The condenser 12 is a heatexchanger for heating a cooling water through heat exchange between thehigh-temperature and high-pressure refrigerant discharged from thecompressor 11 and the cooling water flowing through the heater 25 thatis a heat-exchange target fluid. The high-pressure refrigerant iscondensed when a heat of the high-pressure refrigerant is released tothe cooling water.

The heater 25 includes the condenser 12, a cooling water circulatingcircuit 26, a heater core 27, and a cooling water pump 28. The heater 25heats the ventilation air that is a heat-exchange target fluid using thehigh-pressure refrigerant, as a heat source, discharged from thecompressor 11.

The cooling water flowing through the cooling water circulating circuit26 may be a liquid including at least ethylene glycol,dimethylpolysiloxane, or nano-fluid, or the cooling water may be anantifreeze.

The cooling water circulating circuit 26 is an annular passage throughwhich the cooling water circulates between the condenser 12 and theheater core 27. The condenser 12, the heater core 27, and the coolingwater pump 28 are arranged in this order in the cooling watercirculating circuit 26.

The cooling water pump 28 circulates the cooling water through thecooling water circulating circuit 26 by drawing and discharging thecooling water toward the condenser 12. The cooling water pump 28 is anelectric pump and corresponds to a flow adjuster for the cooling waterthat adjusts a flow rate of the cooling water circulating through thecooling water circulating circuit 26.

The heater core 27 is disposed in a casing 31, as will be describedlater. The heater core 27 heats the ventilation air through heatexchange between the cooling water heated at the condenser 12 and theventilation air that is a heat-exchange target fluid. The condenser 12heats the ventilation air through the heater core 27.

A refrigerant outlet of the condenser 12 is fluidly connected to one ofthree openings of a first three-way joint 13 a. Such three-way joint maybe formed by joining multiple pipes or by defining multiple refrigerantpassages at a metal block or a resin block. The refrigeration cycledevice 10 further includes second to fourth three-way joints 13 b to 13d as described later. Basic structures of the second to fourth three-wayjoints 13 b to 13 d are similar to that of the first three-way joint 13a.

Each of these three-way joints serves as a branching portion or joiningportion. For example, the first three-way joint 13 a in the paralleldehumidification heating mode uses one of the three openings as an inletand the other two of the three openings as outlets. Accordingly, thefirst three-way joint 13 a in the parallel dehumidification heating modeserves as a branching portion that divides a flow of the refrigerantflowing from the one inlet into two flows toward the two outlets.

The fourth three-way joint 13 d in the parallel dehumidification heatingmode uses two of the three openings as inlets and the other one of thethree openings as an outlet. Accordingly, the fourth three-way joint 13d in the parallel dehumidification heating mode serves as a joiningportion that joins refrigerants flowing into the fourth three-way joint13 d through the two inlets and discharges the joined refrigerantthrough the one outlet.

Another opening of the three openings of the first three-way joint 13 ais fluidly connected to a first refrigerant passage 14 a. Therefrigerant flowing out of the condenser 12 is guided toward arefrigerant inlet of the outside evaporator 16 through the firstrefrigerant passage 14 a. The other opening of the three openings of thefirst three-way joint 13 a is fluidly connected to a fourth refrigerantpassage 14 d, and the refrigerant flowing out of the condenser 12 isguided toward an inlet of the second decompression valve 15 b(specifically, one of openings of the third three-way joint 13 c)through the fourth refrigerant passage 14 d. The second decompressionvalve 15 b is disposed in a second refrigerant passage 14 b as describedlater.

The first decompression valve 15 a is disposed in the first refrigerantpassage 14 a. The first decompression valve 15 a can vary an openingarea of the first refrigerant passage 14 a and corresponds to the firstdecompressor that decompresses the refrigerant flowing out of thecondenser 12 at least in the heating mode. The first decompression valve15 a is a variable throttle mechanism including a valve body configuredto vary a throttle degree and an electric actuator including a steppermotor configured to control the throttle degree of the valve body.

The first decompression valve 15 a is configured as a variable throttlemechanism with a full opening function in which the first decompressionvalve 15 a serves as a refrigerant passage without decompressing therefrigerant by fully opening the valve body. An operation of the firstdecompression valve 15 a is controlled by control signals (controlpulse) outputted from the air conditioning controller.

An outlet of the first decompression valve 15 a is fluidly connected tothe refrigerant inlet of the outside evaporator 16. The outsideevaporator 16 exchanges heat between the refrigerant flowing out of thefirst decompression valve 15 a (i.e., out of the condenser 12) and anoutside air blown by a blowing fan (not shown). The outside evaporator16 is disposed at a vehicle front side of the engine compartment. Theblowing fan is an electric blower whose rotational speed (i.e., a blowerperformance) is controlled by a control voltage outputted from the airconditioning controller.

A refrigerant outlet of the outside evaporator 16 is fluidly connectedto the second refrigerant passage 14 b. The second refrigerant passage14 b is a passage through which the refrigerant flowing out of theoutside evaporator 16 flows through the inside evaporator 18 and isguided toward a suction inlet of the compressor 11. The second three-wayjoint 13 b, the non-return valve 17, the third three-way joint 13 c, thesecond decompression valve 15 b, the inside evaporator 18, theevaporating pressure adjusting valve 19, the fourth three-way joint 13d, the accumulator 20, and the low-pressure charging port 23 aredisposed in the second refrigerant passage 14 b in this order along aflow direction of the refrigerant. An end of the second refrigerantpassage 14 b is fluidly connected to the suction inlet of the compressor11.

An opening of the second three-way joint 13 b is fluidly connected tothe third refrigerant passage 14 c through which the refrigerant flowingout of the outside evaporator 16 is guided toward an inlet of theaccumulator 20, as will be described later (specifically, therefrigerant is guided to one of the openings of the fourth three-wayjoint 13 d). The third three-way joint 13 c is fluidly connected to thefourth refrigerant passage 14 d as described above.

The non-return valve 17 allows the refrigerant to flow only from thesecond three-way joint 13 b (i.e., from the outside evaporator 16)toward the inside evaporator 18.

The second decompression valve 15 b is disposed in the secondrefrigerant passage 14 b between the outside evaporator 16 and theinside evaporator 18. In this embodiment, the second decompression valve15 b is disposed in the second refrigerant passage 14 b between thethird three-way joint 13 c and the inside evaporator 18. The seconddecompression valve 15 b is configured to vary an opening area of thesecond refrigerant passage 14 b and corresponds to the seconddecompressor that decompresses the refrigerant flowing out of theoutside evaporator 16 into the inside evaporator 18. A basic structureof the second decompression valve 15 b is the same as that of the firstdecompression valve 15 a. Additionally, the second decompression valve15 b in this embodiment is configured as a variable throttle mechanismwith a full-closing function in which the second refrigerant passage 14b is completely closed when a throttle of the valve is fully closed.

Accordingly, the refrigeration cycle device 10 in this embodiment canswitch the refrigeration circuit by controlling the second decompressionvalve 15 b to close the second refrigerant passage 14 b. In other words,the second decompression valve 15 b serves not only as a refrigerantdecompressor but also as a refrigerant circuit switching device toswitch a refrigerant circuit of the refrigerant circulating through thecycle.

In the cooling, the serial dehumidification heating, and the paralleldehumidification heating modes, the inside evaporator 18 serves as aheat exchanger for cooling that exchanges heat between the refrigerantflowing out of the second decompression valve 15 b (i.e., out of theoutside evaporator 16) and the ventilation air (i.e., a heat-exchangetarget fluid) before passing through the heater core 27. The insideevaporator 18 cools the ventilation air by an endothermic action ofevaporating the refrigerant decompressed by the second decompressionvalve 15 b. The inside evaporator 18 is disposed at a position upstreamof the heater core 27 in a flow direction of the ventilation air in thecasing 31 of the inside air-conditioning unit 30.

The refrigerant passage 14 b is fluidly connected, at a positiondownstream of the inside evaporator 18 in the flow direction of therefrigerant, to an inlet of the evaporating pressure adjusting valve 19.The evaporating pressure adjusting valve 19 adjusts an evaporatingpressure Pe of the refrigerant in the inside evaporator 18 to be equalto or greater than a frost restricting pressure Ape so as to restrict afrost from generating on the inside evaporator 18. In other words, theevaporating pressure adjusting valve 19 adjusts an evaporatingtemperature Te of the refrigerant in the inside evaporator 18 to beequal to or greater than a frost restricting temperature Ate.

In this embodiment, R134a is used as a refrigerant and the frostrestricting temperature Ate is set to have a value slightly higher than0° C. Accordingly, the frost restricting pressure APe is set to have avalue slightly higher than 0.293 MPa that is a saturated pressure ofR134a at 0° C.

The second refrigerant passage 14 b at a position downstream of theevaporating pressure adjusting valve 19 is fluidly connected to thefourth three-way joint 13 d. The fourth three-way joint 13 d is fluidlyconnected to the third refrigerant passage 14 c as described above. Thatis, the third refrigerant passage 14 c has an end connected to thefourth three-way joint 13 d that is a joining portion disposed in thesecond refrigerant passage 14 b between the evaporating pressureadjusting valve 19 and the compressor 11.

The other opening of the fourth three-way joint 13 d is fluidlyconnected to an inlet of the accumulator 20. That is, the accumulator 20is disposed in the second refrigerant passage 14 b between theevaporating pressure adjusting valve 19 and the low-pressure chargingport 23. In this embodiment, the accumulator 20 is disposed at aposition downstream of the fourth three-way joint 13 d that is thejoining portion of the third refrigerant passage 14 c and the secondrefrigerant passage 14 b.

The accumulator 20 defines a buffer space 20 a therein. The accumulator20 is a gas-liquid separator that separates the refrigerant flowingtherein into a gas-phase and a liquid-phase and reserves an excessamount of the refrigerant in the cycle in the buffer space 20 a. Thebuffer space 20 a of the accumulator 20 serves as a reservoir to reservethe excess amount of the refrigerant in the cycle.

The buffer space 20 a of the accumulator 20 increases the capacity of apassage between the low-pressure charging port 23 and the evaporatingpressure adjusting valve 19 as compared when the buffer space 20 a isnot formed. Thus, the buffer space 20 a of the accumulator 20 serves asa pressure change buffer to restrict an inner pressure in the secondrefrigerant passage 14 b from rapidly changing when the refrigerant issupplied into the refrigeration cycle device 10 through the low-pressurecharging port 23.

The accumulator 20 has a gas-phase refrigerant outlet fluidly connectedto the suction inlet of the compressor 11. Accordingly, the accumulator20 restricts the compressor 11 from sucking the liquid-phase refrigerantand prevents a liquid compression in the compressor 11.

The first opening-closing valve 21 is disposed in the third refrigerantpassage 14 c that fluidly connects the second three-way joint 13 b andthe fourth three-way joint 13 d. The first opening-closing valve 21 isan electromagnetic valve as a refrigerant circuit switching device thatswitches a refrigerant circuit, through which the refrigerantcirculates, by selectively opening and closing the third refrigerantpassage 14 c. The first opening-closing valve 21 is an opening-closingmember whose operation is controlled by control signals outputted fromthe air conditioning controller.

The second opening-closing valve 22 is disposed in the fourthrefrigerant passage 14 d that fluidly connects the first three-way joint13 a and the third three-way joint 13 c. The second opening-closingvalve 22 is an electromagnetic valve as a refrigerant circuit switchingdevice that switches a refrigerant circuit, through which therefrigerant circulates, by selectively opening and closing the fourthrefrigerant passage 14 d. A basic structure of the secondopening-closing valve 22 is the same as that of the firstopening-closing valve 21.

The low-pressure charging port 23 is located in the second refrigerantpassage 14 b at a position downstream of the evaporating pressureadjusting valve 19. In this embodiment, the low-pressure charging port23 is located in the second refrigerant passage 14 b between theaccumulator 20 and the compressor 11. The low-pressure charging port 23is used to supply the refrigerant into the refrigeration cycle device 10while operating the compressor 11 after the vehicle (i.e., therefrigeration cycle device 10) is shipped.

The high-pressure charging port 24 is located in the first refrigerantpassage 14 a at a position downstream of the condenser 12. In thisembodiment, the high-pressure charging port 24 is located in the firstrefrigerant passage 14 a between the first three-way joint 13 a and thefirst decompression valve 15 a. The high-pressure charging port 24 isused to supply the refrigerant into the refrigerant cycle device 10before the vehicle (i.e., the refrigeration cycle device 10) is shipped.

Next, the inside air-conditioning unit 30 will be described. The insideair-conditioning unit 30 conveys the ventilation airtemperature-adjusted by the refrigeration cycle device 10 into thevehicle cabin that is an air-conditioning target space. The insideair-conditioning unit 30 is disposed in an instrument panel that definesthe most front side of the vehicle cabin. The inside air conditioningunit 30 includes a blower 32, the inside evaporator 18, and the heatercore 27 in the casing 31 constituting an outer frame thereof.

The casing 31 is an air passage forming portion that defines a passageof the ventilation air conveyed to the vehicle cabin that is anair-conditioning target space. The casing 31 is made of resin such aspolypropylene having a certain degree of an elasticity and greatstrength. An inside outside air switching device 33 is located at themost upstream side in the casing in the flow of the ventilation air. Theinside outside air switching device 33, as an inside outside switchingportion, switches air introduced into the casing between an inside air(i.e., air inside the air-conditioning target space) and an outside air(i.e., air outside the air-conditioning target space).

The blower 32 is located at a position downstream of the inside outsideair switching device 33 in the flow direction of the ventilation air.The blower 32 blows an air drawn through the inside outside airswitching device 33 toward the air-conditioning target space. The blower32 is an electric blower that drives a centrifugal multi blades fan(i.e., sirocco fan) by an electric motor. The rotational speed (i.e., aflow rate) of the blower 32 is controlled by a control voltage outputtedfrom the air conditioning controller.

The inside evaporator 18 is disposed in the air passage defined by thecasing 31 at a position downstream of the blower 32 in the flowdirection of the ventilation air. A space downstream of the insideevaporator 18 in the air passage defined by the casing 31 is dividedinto two spaces so that an inside condenser passage 35 and a cooling airbypass passage 36 are formed in parallel with each other.

The heater core 27 is disposed in the inside condenser passage 35. Thatis, the inside condenser passage 35 is a passage through which theventilation air flows to exchange its heat with the refrigerant at theheater core 27. The inside evaporator 18 and the heater core 27 arearranged in this order in the flow direction of the ventilation air. Inother words, the inside evaporator 18 is located upstream of the heatercore 27 in the flow direction of the ventilation air.

The cooling air bypass passage 36 is a passage through which theventilation air that has passed through the inside evaporator 18 flowswhile bypassing the heater core 27.

An air mix door 34 is disposed at a position downstream of the insideevaporator 18 and upstream of the heater core 27 in the flow directionof the ventilation air. The air mix door 34 is a flow ratio adjusterthat adjusts an amount of the ventilation air passing through the heatercore 27 that has passed through the inside evaporator 18 based oncontrol signals outputted from the air conditioning controller.

A mixing passage 37 is defined in the casing 31 at a position downstreamof the inside condenser passage 35 and the cooling air bypass passage36. The ventilation air heated at the heater core 27 is mixed with theventilation air flowing through the cooling air bypass passage 36without being heated at the heater core 27 in the mixing passage 37.

Multiple openings are defined at the most downstream side of the casing31 in the flow direction of the ventilation air. The ventilation air(i.e., conditioned air) mixed at the mixing passage 37 is conveyedtoward the vehicle cabin through the multiple openings.

The air mix door 34 adjusts the ratio of an amount of air passingthrough the heater core 27 and an amount of air flowing through thecooling air bypass passage 36, and therefore a temperature of theconditioned air mixed in the mixing passage 37 is adjusted. As a result,a temperature of the conditioned air conveyed into the vehicle cabinthat is an air-conditioning target space is adjusted.

That is, the air mix door 34 serves as a temperature adjuster thatadjusts a temperature of the conditioned air blown into the vehiclecabin that is an air-conditioning target space. The air mix door 34 isdriven by an electric actuator for the air mix door 34. The operation ofthe electric actuator is controlled by control signals outputted fromthe air conditioning controller.

The air mix door 34 causes the ventilation air to flow through theinside evaporator 18 and the heater core 27 in this order during theheating mode, the serial dehumidification heating mode, and the paralleldehumidification heating mode. The air mix door 34 causes theventilation air to flow through the inside evaporator 18 and bypass theheater core 27 during the cooling mode. The air mix door 34 serves as anair passage switching device.

Next, an operation of the air conditioner 1 in this embodiment will bedescribed. The air conditioner 1 in this embodiment can switch theoperating mode between the heating mode, the cooling mode, the serialdehumidification heating mode, and the parallel dehumidification heatingmode. These operating modes are selectively switched by executingair-conditioning control programs stored in the air conditioningcontroller in advance.

(a) Heating Mode

In the heating mode, the air conditioning controller opens the firstopening-closing valve 21, closes the second opening-closing valve 22,controls the first decompression valve 15 a to serve as a decompressorby reducing a throttle of the first decompression valve 15 a, and fullycloses the second decompression valve 15 b.

In the heating mode, as shown by the black arrows in FIG. 1, therefrigeration cycle device 10 constitutes the vapor compression typerefrigeration cycle through which the refrigerant circulates through thecompressor 11, the condenser 12, the first decompression valve 15 a, theoutside evaporator 16, the first opening-closing valve 21, theaccumulator 20, and the compressor 11 again in this order.

In this cycle, the air conditioning controller appropriately controlsoperations of air conditioning devices connected to an output portion ofthe air conditioning controller. The air conditioning controllerdetermines control signals outputted to the electric actuator for theair mix door 34 such that the air mix door 34 completely closes thecooling air bypass passage 36. That is, the control signals aredetermined such that all of the ventilation air that has passed throughthe inside evaporator 18 flows through the air passage in which theheater core 27 is disposed.

Accordingly, in the refrigeration cycle device 10 in the heating mode,the high-pressure refrigerant discharged from the compressor 11 flowsinto the condenser 12. The refrigerant flowing through the condenser 12exchanges heat with the cooling water flowing through the cooling watercirculating circuit 26 and releases the heat. As a result, the coolingwater flowing through the cooling water circulating circuit 26 isheated. The ventilation air that has been blown by the blower 32 andpassed through the inside evaporator 18 is heated at the heater core 27because the air mix door 34 opens the air passage in which the heatercore 27 is disposed.

The refrigerant flowing out of the condenser 12 flows through the firstthree-way joint 13 a toward the first refrigerant passage 14 a becausethe second opening-closing valve 22 is closed. The refrigerant flowingthrough the first refrigerant passage 14 a is decompressed to be alow-pressure refrigerant by the first decompression valve 15 a. Thelow-pressure refrigerant decompressed by the first decompression valve15 a flows into the outside evaporator 16 and absorbs heat from anoutside air blown by the blowing fan.

The refrigerant flowing out of the outside evaporator 16 flows throughthe second three-way joint 13 b toward the third refrigerant passage 14c because the first opening-closing valve 21 is opened and the seconddecompression valve 15 b is completely closed. The refrigerant flowingthrough the third refrigerant passage 14 c flows through the fourththree-way joint 13 d into the accumulator 20 and is separated into agas-phase and a liquid-phase. The gas-phase refrigerant separated in theaccumulator 20 is sucked by the compressor 11 through the suction inletand compressed again by the compressor 11.

Accordingly, in the heating mode, the ventilation air heated at theheater core 27 through the condenser 12 is blown into the vehicle cabinthat is an air-conditioning target space to perform an air-heating inthe vehicle cabin.

(b) Cooling Mode

In the cooling mode, the air conditioning controller closes the firstopening-closing valve 21 and the second opening-closing valve 22, fullyopens the first decompression valve 15 a, and reduces the throttle ofthe second decompression valve 15 b.

In the cooling mode, as shown by white arrows in FIG. 1, therefrigeration cycle device 10 constitutes a vapor compression typerefrigeration cycle through which the refrigerant circulates through thecompressor 11, the condenser 12, the first decompression valve 15 a, theoutside evaporator 16, the non-return valve 17, the second decompressionvalve 15 b, the inside evaporator 18, the evaporating pressure adjustingvalve 19, the accumulator 20, and the compressor 11 again in this order.

In this cycle, the air conditioning controller appropriately controlsthe air conditioning devices connected to the output portion of the airconditioning controller. The control signals outputted to the electricactuator for the air mix door 34 from the air conditioning controllerare set such that the air mix door 34 fully opens the cooling air bypasspassage 36. Thus, all amount of the ventilation air that has passedthrough the inside evaporator 18 flows through the cooling air bypasspassage 36.

Accordingly, in the refrigeration cycle device 10 in the cooling mode,the high-pressure refrigerant discharged from the compressor 11 flowsinto the condenser 12. At this time, the air mix door 34 completelycloses the air passage in which the heater core 27 is disposed, thus thecooling water flowing through the heater core 27 rarely exchanges heatwith the ventilation air and flows out of the heater core 27.

The refrigerant flowing out of the condenser 12 flows through the firstthree-way joint 13 a toward the first refrigerant passage 14 a becausethe second opening-closing valve 22 is closed. The refrigerant flowingthrough the first refrigerant passage 14 a flows into the firstdecompression valve 15 a. At this moment, the refrigerant flowing out ofthe condenser 12 is not decompressed by the first decompression valve 15a and flows into the outside evaporator 16 because the firstdecompression valve 15 a is fully opened.

The refrigerant flowing through the outside evaporator 16 releases heatto the outside air blown by the blowing fan at the outside evaporator16. The refrigerant flowing out of the outside evaporator 16 flowsthrough the second three-way valve 13 b toward the second refrigerantpassage 14 b because the first opening-closing valve 21 is closed. Therefrigerant flowing through the second refrigerant passage 14 b isdecompressed to be a low-pressure refrigerant by the seconddecompression valve 15 b.

The low-pressure refrigerant decompressed by the second decompressionvalve 15 b flows into the inside evaporator 18 and evaporates byabsorbing heat from the ventilation air blown by the blower 32. Thus,the ventilation air is cooled. The refrigerant flowing out of the insideevaporator 18 flows through the evaporating pressure adjusting valve 19into the accumulator 20 and is separated into a gas-phase and aliquid-phase in the accumulator 20. The gas-phase refrigerant separatedat the accumulator 20 is sucked by the compressor 11 through the suctioninlet and compressed by the compressor 11 again.

Accordingly, in the cooling mode, the ventilation air cooled at theinside evaporator 18 is blown into the vehicle cabin that is anair-conditioning target space, thereby performing an air-cooling in thevehicle cabin.

(c) Serial Dehumidification Heating Mode

In the serial dehumidification heating mode, the air conditioningcontroller closes the first opening-closing valve 21 and the secondopening-closing valve 22 and reduces throttles of the firstdecompression valve 15 a and the second decompression valve 15 b. Theair conditioning controller displaces the air mix door 34 such that theair passage in which the heater core 27 is disposed is fully opened andthe cooling air bypass passage 36 is fully closed.

The refrigeration cycle device 10 in the serial dehumidification heatingmode constitutes a vapor compression type refrigeration cycle, as shownby white arrows in FIG. 1, in which the refrigerant circulates throughthe compressor 11, the condenser 12, the first decompression valve 15 a,the outside evaporator 16, the non-return valve 17, the seconddecompression valve 15 b, the inside evaporator 18, the evaporatingpressure adjusting valve 19, the accumulator 20, and the compressor 11again in this order. That is, the outside evaporator 16 and the insideevaporator 18 is serially connected in the flow direction of therefrigerant.

The refrigeration cycle device 10 in the serial dehumidification heatingmode constitutes a refrigeration cycle in which the condenser 12 servesas a radiator and the inside evaporator 18 serves as an evaporator. Whena saturated temperature of the refrigerant in the outside evaporator 16is higher than an outside temperature Tam, the outside evaporator 16serves as a radiator. When the saturated temperature of the refrigerantin the outside evaporator 16 is lower than the outside temperature Tam,the outside evaporator 16 serves as an evaporator.

In this cycle, the air conditioning controller appropriately controlsoperations of the air conditioning devices connected to the outputportion of the air conditioning controller. The control signalsoutputted to the electric actuator for the air mix door 34 from the airconditioning controller are set such that the air mix door 34 completelycloses the cooling air bypass passage 36 as with in the heating mode.That is, the control signals are determined such that all amount of theair having passed through the inside evaporator 18 flows through the airpassage in which the heater core 27 is disposed.

Accordingly, in the serial dehumidification heating mode, theventilation air cooled and dehumidified at the inside evaporator 18 isheated at the heater core 27 and blown into the vehicle cabin that is anair-conditioning target space. Thus, air in the vehicle cabin isdehumidified and heated. Additionally, a heating capacity of the heatercore 27 for the ventilation air can be adjusted by adjusting thethrottle degrees of the first decompression valve 15 a and the seconddecompression valve 15 b.

(d) Parallel Dehumidification Heating Mode

In the parallel dehumidification heating mode, the air conditioningcontroller opens the first opening-closing valve 21 and the secondopening-closing valve 22 and reduces the throttles of the firstdecompression valve 15 a and the second decompression valve 15 b.

As shown by arrows with diagonal hatching in FIG. 1, the refrigerationcycle device in the parallel dehumidification heating mode constitutes avapor compression type refrigeration cycle in which the refrigerantcirculates through the compressor 11, the condenser 12, the firstdecompression valve 15 a, the outside evaporator 16, the firstopening-closing valve 21, the accumulator 20, and the compressor 11, andthe refrigerant also circulates through the compressor 11, the condenser12, the second opening-closing valve 22, the second decompression valve15 b, the inside evaporator 18, the evaporating pressure adjusting valve19, the accumulator 20, and the compressor 11 in this order.

That is, in the parallel dehumidification heating mode, the flow of therefrigerant flowing out of the condenser 12 is separated into two flowsat the first three-way joint 13 a. One of the two flows of therefrigerant flows through the first decompression valve 15 a, theoutside evaporator 16, and the compressor 11 in this order, and theother one of the two flows of the refrigerant flows through the seconddecompression valve 15 b, the inside evaporator 18, the evaporatingpressure adjusting valve 19, and the compressor in this order.

In this cycle, the air conditioning controller appropriately controlsoperations of the air conditioning devices connected to the outputportion of the air conditioning controller. For example, the controlsignals outputted to the electric actuator for the air mix door 34 fromthe air conditioning controller are set such that the air mix door 34fully closes the cooling air bypass passage 36 as with in the heatingmode. That is, the control signals are determined such that the allamount of the ventilation air having passed through the insideevaporator 18 flows through the air passage in which the heater core 27is disposed.

Accordingly, in the refrigeration cycle device 10 in the paralleldehumidification heating mode, the high-pressure refrigerant dischargedfrom the compressor 11 flows into the condenser 12. The refrigerantflowing in the condenser 12 exchanges heat with and releases heat to thecooling water. The ventilation air that has been blown by the blower 32and passed through the inside evaporator 18 is heated by the coolingwater heated by the refregerant similarly to the heating mode becausethe air mix door 34 opens the air passage in which the heater core 27 isdisposed. As a result, the ventilation air is heated.

The second opening-closing valve 22 is opened, thus the flow of therefrigerant flowing out of the condenser 12 is separated into the twoflows at the first three-way joint 13 a. One of the two flows of therefrigerant separated at the first three-way joint 13 a flows throughthe first refrigerant passage 14 a. The refrigerant flowing through thefirst refrigerant passage 14 a is decompressed to be a low-pressurerefrigerant at the first decompression valve 15 a. The low-pressurerefrigerant decompressed by the first decompression valve 15 a flowsinto the outside evaporator 16 and absorbs heat from an outside airblown by the blowing fan.

The other one of the two flows of the refrigerant separated at the firstthree-way joint 13 a flows through the fourth refrigerant passage 14 d.The refrigerant flowing through the fourth refrigerant passage 14 d isrestricted from flowing back toward the outside evaporator 16 by thenon-return valve 17 and flows through the second opening-closing valve22 and the third three-way joint 13 c into the second decompressionvalve 15 b.

The refrigerant flowing through the second decompression valve 15 b isdecompressed to be a low-pressure refrigerant. The low-pressurerefrigerant decompressed by the second decompression valve 15 b flowsinto the inside evaporator 18 and evaporates by absorbing heat from theventilation air blown by the blower 32. As a result, the ventilation airis cooled. The refrigerant flowing out of the inside evaporator 18 isdecompressed by the evaporating pressure adjusting valve 19 to have avalue substantially equal to the pressure of the refrigerant flowing outof the outside evaporator 16.

The refrigerant flowing out of the evaporating pressure adjusting valve19 flows through the fourth three-way joint 13 d and merges with therefrigerant flowing out of the outside evaporator 16. The refrigerantmerging at the fourth three-way joint 13 d flows into the accumulator 20and is separated into a gas-phase and a liquid-phase. The gas-phaserefrigerant separated at the accumulator 20 is sucked by the compressor11 through the suction inlet and compressed again by the compressor 11.

In the parallel dehumidification heating mode, the ventilation aircooled and dehumidified at the inside evaporator 18 is heated at theheater core 27 and blown into the vehicle cabin that is anair-conditioning target space. As a result, air in the vehicle cabin isdehumidified and heated.

In addition, in the parallel dehumidification heating mode in thisembodiment, the evaporating temperature of the refrigerant in theoutside evaporator 16 can be lowered than the evaporating temperature inthe inside evaporator 18. Accordingly, a temperature difference betweenthe evaporating temperature of the refrigerant in the outside evaporator16 and the outside air can be increased, thereby increasing an amount ofair absorbed by the refrigerant at the outside evaporator 16.

As a result, the heating capacity of the heater core 27 for theventilation air can be increased compared to a refrigeration cycledevice in which the evaporating temperature of the refrigerant in theoutside evaporator 16 is similar to the evaporating temperature of therefrigerant in the inside evaporator 18.

As described above, the refrigeration cycle device 10 in this embodimentcan perform a comfortable air-heating in the vehicle cabin byselectively switching the operating mode between the heating mode, thecooling mode, the serial dehumidification heating mode, and the paralleldehumidification heating mode.

Next, a method to supply the refrigerant into the refrigeration cycledevice 10 will be described. Before the air conditioner 1 (i.e., therefrigeration cycle device 10) is shipped out, the first decompressionvalve 15 a and the second decompression valve 15 b are fully opened. Therefrigeration cycle device 10 is vacuumed through the high-pressurecharging port 24 and the low-pressure charging port 23 while opening thefirst opening-closing valve 21 and the second opening-closing valve 22.

The refrigeration cycle device 10 is vacuumed to remove air in therefrigeration cycle device 10. If air is remained in the refrigerationcycle device 10, water vapor in the air would freeze in therefrigeration cycle device 10, which prevents the refrigerant fromcirculating through the refrigeration cycle device 10.

After the refrigeration cycle device 10 is vacuumed, the firstdecompression valve 15 a and the second decompression valve 15 b arefully opened. The refrigerant is supplied into the refrigeration cycledevice 10 through the high-pressure charging port 24 while opening thefirst opening-closing valve 21 and the second opening-closing valve 22.

After shipping out the air conditioner 1 (i.e., the refrigeration cycledevice 10), the first decompression valve 15 a and the seconddecompression valve 15 b are fully opened. The refrigerant is suppliedinto the refrigeration cycle device 10 through the low-pressure chargingport 23 while opening the first opening-closing valve 21 and the secondopening-closing valve 22 and operating the compressor 11.

As described above, the accumulator 20 is disposed in the secondrefrigerant passage 14 b between the evaporating pressure adjustingvalve 19 and the low-pressure charging port 23. The accumulator 20,which is a pressure change buffer, restricts an inner pressure in thesecond refrigerant passage 14 b from rapidly changing when therefrigerant is supplied through the low-pressure charging port 23.

The accumulator 20 defines the buffer space 20 a, thereby restrictingthe inner pressure in the second refrigerant passage 14 b from rapidlychanging when the refrigerant is supplied into the refrigeration cycledevice 10 through the low-pressure charging port 23 and the secondrefrigerant passage 14 b. The reason why the rapid change in the innerpressure is avoided is that the air in the buffer space 20 a iscompressed. Thus, it is possible to suppress a pressure change at anoutlet side of the evaporating pressure adjusting valve 19. In addition,even though the low-pressure charging port 23 is disposed at a positiondownstream of the evaporating pressure adjusting valve 19, a durabilityof the evaporating pressure adjusting valve 19 is restricted from beingimpaired.

The refrigeration cycle device 10 in this embodiment can improve aflexibility of positions at which the charging port is mounted withoutimpairing the durability of the evaporating pressure adjusting valve.

The buffer space 20 a is defined by the accumulator 20 that is areservoir to reserve an excess amount of the refrigerant. The bufferspace 20 a of the accumulator 20 that has been already installed as areservoir in the refrigeration cycle device 10 is used as a pressurechange buffer, thus an additional pressure change buffer is not needed.Therefore, a cost and a size of the refrigeration cycle device 10 arenot increased. The refrigeration cycle device 10 that keeps thedurability of the evaporating pressure adjusting valve 19 can beprovided even though the low-pressure charging port 23 is located at aposition downstream of the evaporating pressure adjusting valve 19.

Second Embodiment

Hereinafter, a refrigeration cycle device 10 in a second embodiment willbe described with reference to FIG. 2 mainly at points different fromthe refrigeration cycle device 10 in the first embodiment. In therefrigeration cycle device 10 in the second embodiment, a muffler 51 isdisposed in the second refrigerant passage 14 b between the evaporatingpressure adjusting valve 19 and the low-pressure charging port 23. Inthis embodiment, the muffler 51 is disposed in the second refrigerantpassage 14 b between the accumulator 20 and the low-pressure chargingport 23.

The muffler 51 defines a buffer space 51 a that reduces a pressurepulsation generated when the compressor 11 discharges the refrigerant.The buffer space 51 a also serves as a pressure change buffer thatrestricts the inner pressure in the second refrigerant passage 14 b fromchanging when the refrigerant is supplied into the second refrigerantpassage 14 b through the low-pressure charging port 23.

The buffer space 51 a of the muffler 51 increases the capacity of apassage through which the refrigerant flows between the evaporatingpressure adjusting valve 19 and the low-pressure charging port 23. Thus,air in the buffer space 51 a is compressed when the refrigerant issupplied into the second refrigerant passage 14 b through thelow-pressure charging port 23, thereby further restricting the innerpressure in the second refrigerant passage 14 b from rapidly increasing.Thus, the pressure of the second refrigerant passage 14 b at a positiondownstream of the evaporating pressure adjusting valve 19 is furtherrestricted from changing.

As described above, the buffer space 51 a is configured with the muffler51 that reduces the pressure pulsation generated when the compressor 11discharges the refrigerant. The refrigeration cycle device 10 includingthe muffler 51 does not need an additional member as a pressure changebuffer. Thus, the refrigeration cycle device 10 can keep the durabilityof the evaporating pressure adjusting valve 19 without increasing a costand a size of the refrigeration cycle device 10 even though thelow-pressure charging port 23 is disposed at a position downstream ofthe evaporating pressure adjusting valve 19. The pressure in the secondrefrigerant passage 14 b at a position downstream of the evaporatingpressure adjusting valve 19 is further restricted from changing when therefrigerant is supplied into the refrigeration cycle device 10 throughthe low-pressure charging port 23.

Third Embodiment

A refrigeration cycle device 10 in a third embodiment will be describedwith reference to FIG. 3 mainly at different points from the firstembodiment. The refrigeration cycle device 10 in the third embodimentincludes a buffer space 52, as a pressure change buffer, defined in aportion of the second refrigerant passage 14 b between the evaporatingpressure adjusting valve 19 and the low-pressure charging port 23. Inthis embodiment, the buffer space 52 is defined in a portion of thesecond refrigerant passage 14 b between the accumulator 20 and thelow-pressure charging port 23.

The buffer space 52 is defined by repeatedly bending a pipe. The bufferspace 52 increases a length of a passage through which the refrigerantflows between the evaporating pressure adjusting valve 19 and thelow-pressure charging port 23 and increases the capacity of the passagethrough which the refrigerant flows.

The buffer space 52 may be defined by branching multiple pipes andjoining these multiple pipes to increase the capacity of the passagethrough which the refrigerant flows.

The buffer space 52 increases the capacity of the passage through whichthe refrigerant flows between the evaporating pressure adjusting valve19 and the low-pressure charging port 23. When the refrigerant issupplied into the refrigeration cycle device 10 through the low-pressurecharging port 23 and the second refrigerant passage 14 b, air in thebuffer space 52 is compressed. Thus, the inner pressure in the secondrefrigerant passage 14 b is further restricted from rapidly changing. Asa result, a pressure in the second refrigerant passage 14 b downstreamof the evaporating pressure adjusting valve 19 is further restrictedfrom changing.

As described above, the buffer space 52 is defined by the pipe.Accordingly, a structure to restrict a pressure at the outlet side ofthe evaporating pressure adjusting valve 19 from changing can beachieved at a low cost.

The present disclosure is not limited to the embodiments describedabove, and can be variously modified in a range without departing from agist of the present disclosure.

In the above embodiments, the refrigeration cycle device 10 in thepresent disclosure is applied to the vehicle, but the refrigerationcycle device 10 is not limited to a device for a vehicle and may beapplied to a stationary refrigeration cycle device.

Components of the refrigeration cycle device 10 are not limited to thosedescribed in the embodiments. In the embodiments, the compressor 11 isan electric compressor, but not limited to this. When the compressor 11is used for an engine for vehicle driving, the compressor 11 may be anengine driven compressor that is driven by a rotational driving forcetransmitted by the engine through a pulley and a belt.

Means disclosed in the above embodiments can be combined with each otherin a practical range. For example, the air conditioner may be configuredby combining the refrigeration cycle device 10 in the second embodimentand the refrigeration cycle device 10 in the third embodiment.

The low-pressure charging port 23 may include a throttle such as anorifice to further restrict a pressure at a position downstream of theevaporating pressure adjusting valve 19 from changing when therefrigerant is supplied into the refrigeration cycle device 10 throughthe low-pressure charging port 23.

A method to supply the refrigerant into the refrigeration cycle device10 after the air conditioner 1 (i.e., the refrigeration cycle device 10)is shipped out is not limited to the method described above.Hereinafter, another method will be described.

At first, a predetermined amount of the refrigerant is supplied into therefrigeration cycle device 10 through the high-pressure charging port 24while fully opening the first decompression valve 15 a and the seconddecompression valve 15 b and opening the first opening-closing valve 21and the second opening-closing valve 22.

Next, the refrigerant is further supplied into the refrigeration cycledevice 10 through the low-pressure charging port 23 while completelyclosing the high-pressure charging port 24 and operating the compressor11.

After the predetermined amount of the refrigerant is supplied into therefrigeration cycle device 10 through the high-pressure charging port 24as described above, the refrigerant is further supplied through thelow-pressure charging port 23.

In this case, when the refrigerant is supplied into the refrigerationcycle device 10 through the low-pressure charging port 23, thepredetermined amount of the refrigerant has been already supplied intothe refrigeration cycle device 10. Accordingly, a pressure differencebetween the refrigerant supplied into the refrigeration cycle device 10through the low-pressure charging port 23 and the refrigerant in therefrigeration cycle device 10 can be decreased. Thus, a counter pressureis not likely to act on the evaporating pressure adjusting valve 19while the refrigerant is supplied into the refrigeration cycle device 10through the low-pressure charging port 23.

Therefore, a pressure at the outlet side of the evaporating pressureadjusting valve 19 is further restricted from rapidly changing when therefrigerant is supplied into the refrigeration cycle device 10 throughthe low-pressure charging port 23.

The predetermined amount of the refrigerant supplied into therefrigeration cycle device 10 through the high-pressure charging port 24is predetermined such that the pressure at a position downstream of theevaporating pressure adjusting valve 19 is restricted from rapidlychanging when the refrigerant is supplied into the second refrigerantpassage 14 b through the low-pressure charging port 23.

Although the present disclosure has been described in accordance withthe examples, it is understood that the disclosure is not limited tosuch examples or structures. The present disclosure encompasses variousmodifications and variations within the scope of equivalents. Inaddition, it should be understood that various combinations or aspects,or other combinations or aspects, in which only one element, one or moreelements, or one or less elements are added to the various combinationsor aspects, also fall within the scope or technical idea of the presentdisclosure.

What is claimed is:
 1. A refrigeration cycle device comprising: acompressor configured to compress and discharge a refrigerant; a heaterconfigured to heat a heat-exchange target fluid using the refrigerant,as a heat source, discharged from the compressor; an outside evaporatorconfigured to exchange heat between an outside air and the refrigerantflowing out of the heater; an inside evaporator configured to exchangeheat between the refrigerant flowing out of the outside evaporator andthe heat-exchange target fluid; a first refrigerant passage throughwhich the refrigerant flowing out of the heater is guided toward aninlet of the outside evaporator; a first decompressor disposed in thefirst refrigerant passage and configured to vary an opening area of thefirst refrigerant passage; a second refrigerant passage through whichthe refrigerant flowing out of the outside evaporator passes through theinside evaporator and is guided toward a suction inlet of thecompressor; a second decompressor disposed in the second refrigerantpassage between the outside evaporator and the inside evaporator andconfigured to vary an opening area of the second refrigerant passage; anevaporating pressure adjusting valve disposed in the second refrigerantpassage at a position downstream of the inside evaporator and configuredto adjust an evaporating pressure of the refrigerant in the insideevaporator; a third refrigerant passage having an end fluidly connectedto a portion of the second refrigerant passage between the evaporatingpressure adjusting valve and the compressor, the refrigerant flowing outof the outside evaporator being guided toward the suction inlet of thecompressor through the third refrigerant passage; an opening-closingmember configured to selectively open and close the third refrigerantpassage; a charging port disposed in the second refrigerant passage at aposition downstream of the evaporating pressure adjusting valve tosupply the refrigerant therethrough; and a pressure change bufferdisposed in the second refrigerant passage between the evaporatingpressure adjusting valve and the charging port, the pressure changebuffer defining a buffer space therein to restrict an inner pressure inthe second refrigerant passage from rapidly changing when therefrigerant is supplied through the charging port.
 2. The refrigerationcycle device according to claim 1, wherein the buffer space is definedby a reservoir that reserves an excess amount of the refrigerant.
 3. Therefrigeration cycle device according to claim 1, wherein the bufferspace is defined by a muffler that is configured to reduce a pressurepulsation generated when the refrigerant is discharged from thecompressor.
 4. The refrigeration cycle device according to claim 1,wherein the buffer space is defined by a pipe.